Description
Kasugamycin is an aminoglycosidic antibiotic isolated from
S. kasugaensis. It blocks the initiation of translation, preventing initiation complex formation on 30S ribosomes in bacteria.
1
Uses
kasugamycin, derived from Streptomyces kasuguensis, is also used to
control rice blast.It acts by inhibiting protein synthesis
by interfering with the binding of aminoacyl-tRNA to the mRNA-30s
ribosomal subunit complex (Yamaguchi, 1998).
in vitro
kasugamycin could inhibit protein synthesis by interacting with the 30s ribosomal subunit. the mechanism of inhibition of protein synthesis appeared to be different from that of other aminoglycosides, such as kanamycin, streptomycin, neomycin, gentamicin. the initiation complex formation on 30s ribosomes could be inhibited by kasugamycin but not by streptomycin, kanamycin or gentamicin, though the binding of fmet-trna to 70s ribosomes was inhibited by both streptomycin and by kasugamycin. [1].
in vivo
five groups, each consisting of five guinea pigs, were infected with shibaura strain; two groups were treated by injection with kasugamycin. all animals treated with 1 mcg/g were killed showing an average survival period of 7.4 days, which was close to the average survival period of 6.2 days in the control group; while all animals treated with 5 mcg/g survived. the other two groups were treated with kasugamycin from the icteric stage to the 10th day after infection. two animals of the 5 mcg/g group survived, showing no leptospira in the kidney; the other three died in an average of 7.7 days. three animals of the 10 mcg/g group survived; while the other two animals died in 6.5 days on an average . the total amounts of kasugamycin administered to the infected guinea pigs from the febrile stage were 10.8 mg (the 1 mcg/g group) and 54.0 mg (the 5 mcg/g group) [2].
Metabolic pathway
kasugamycin hydrochloride hydrate is a relatively stable antibiotic. There
is limited published information on its metabolism and environmental
fate but it is extensively degraded in plants and soil as indicated in
Scheme 1.
Degradation
kasugamycin hydrochloride hydrate is very stable at room temperature.
It is stable in weak acids but unstable in strong acids and under basic
conditions. Its DT50 values at 50 °C are 47 and 14 days at pH 5 and 9,
respectively (PM).
References
[1] okuyama, a. ,machiyama, n.,kinoshita, t., et al. inhibition by kasugamycin of initiation complex formation on 30s ribosomes. biochemical and biophysical research communications 43(1), 196-199 (1971).
[2] kitaoka m, mori m, arimitsu y. in vitro and in vivo effects of kasugamycin on leptospira icterohaemorrhagiae. jpn j med sci biol. 1975 oct-dec;28(5-6):285-90.